1. Field of the Invention
This invention relates to so-called karaoke system, and more particularly to karaoke system capable of managing playing time of karaoke songs utilizing data recorded according to MIDI (Musical Instrument Digital Interface) standard.
2. Description of the Prior Art
Conventionally, there are known karaoke systems constructed as illustrated in FIGS. 1 and 2. FIG. 1 illustrates construction of system called "LVD karaoke system". This LVD karaoke system K.sub.1 includes an LVD auto-changer PL.sub.1, a commander CM.sub.1, an operation unit CB.sub.1, an amplifier AM.sub.1, speakers SP.sub.1 and SP.sub.2, an image display device GD.sub.1 and a microphone MC.sub.1. The LVD auto-changer PL.sub.1 reproduces information from a plurality of laser video disks D.sub.1, serving as karaoke information recording media, housed therein. The commander CM.sub.1 controls the LVD auto-changer PL.sub.1 to select a laser video disk D.sub.1 in the LVD auto-changer PL.sub.1 in response to request of songs input via the operation unit CB.sub.1. The image display unit GD.sub.1 displays image of reproduced image signal. The microphone MC.sub.1 converts singing voice into an audio signal and outputs it to the amplifier AM.sub.1. The amplifier AM.sub.1 mixes audio signal, serving as karaoke signal, from the LVD auto-changer PL.sub.1 with the audio signal of singing voice supplied from the microphone MC.sub.1, and outputs the mixed audio signal to the speakers SP.sub.1 and SP.sub.2. The speakers SP.sub.1 and SP.sub.2 output the mixed audio signal as acoustic sound. The commander CM.sub.1 may includes the operation unit CB.sub.1 in it.
FIG. 2 illustrates construction of system called "CD karaoke system". This CD karaoke system K.sub.2 includes a CD auto-changer PL.sub.2, a commander CM.sub.2, an operation unit CB.sub.2, an amplifier AM.sub.2, speakers SP.sub.3 and SP.sub.4, a graphic decoder DE, an image display device GD.sub.2 and a microphone MC.sub.2. The CD auto-changer PL.sub.2 reproduces information from a plurality of compact disks D.sub.2, serving as karaoke information recording media, housed therein. The commander CM.sub.2 controls the CD auto-changer PL.sub.2 to select a compact disk D.sub.2 in the CD auto-changer PL.sub.2 in response to a request of songs input via the operation unit CB.sub.2. The graphic decoder DE converts graphic data obtained from subcode data in the compact disk D.sub.2 into image signal, and the image display unit GD.sub.2 displays image of the image signal. The microphone MC.sub.2 converts singing voice into an audio signal and outputs it to the amplifier AM.sub.2. The amplifier AM.sub.2 mixes audio signal, serving as karaoke signal, from the CD auto-changer PL.sub.2 with the audio signal of singing voice supplied from the microphone MC.sub.2, and outputs the mixed audio signal to the speakers SP.sub.3 and SP.sub.4. The speakers SP.sub.3 and SP.sub.4 output the mixed audio signal as acoustic sound. The commander CM.sub.2 may includes the operation unit CB.sub.2 and the graphic decoder DE in it. Using the systems described above, user can sing a song with accompaniment of karaoke music and enjoy images displayed simultaneously. The above-described karaoke system obtains playing time data of songs from data recorded in laser video disk D.sub.1 or compact disk D.sub.2, and simply displays playing time of each songs and total playing time.
Recently there is a business known as "Karaoke Box" or "Karaoke Room". In such a business, user rents a room in which karaoke system is installed, enjoys singing karaoke songs, and pays for use of the room by the hour. User decides playing time of karaoke system (i.e., how long user enjoys karaoke in the room) in advance and clerks of the karaoke room notifies ending of the time to the user. However, in use of the above-described karaoke system, user sometimes makes reservation of karaoke songs without considering how long the playing time remains. Therefore, user is difficult to know how many songs he can sing within the remaining playing time. Sometimes, all reserved songs cannot played within the remaining playing time and user leaves the karaoke room with some reserved songs remained unsung. This is not preferable in view of management of karaoke box and service to users.